What

When style, which defines popover position, is not set, popover is rendered at the end of document.body. After initial render, popover get its trigger and content dimensions and recalculates style to correct one. It causes temporarily visible blinking effect when popover is rendered in lower left part of the screen and then in correct position (see below screencast).

Similar thing happens when try to open same popover twice. On first opening, it calculates its position and store it in state. But if popover's trigger position changes, we can see blinking again, because popover renders on old position and then re-renders itself to correct position (see screencast).

To fix first problem, when style is empty, default style is used that is outside viewport. That way, user can't see first render and sees only popover in correct position.
Similarly, second problem is fixed by resetting style on each close.

Testing

• Is this change covered by the unit tests?

• Is this change covered by the integration tests?

• Is this change covered by the automated acceptance tests? (if applicable)

Compatibility

• Does this change maintain backward compatibility?

Screenshots

Before

After